HVAC-Talk: Heating, Air & Refrigeration Discussion banner
Cancel
Create thread New Forums

ABB VSD

Jump to Latest
1 - 18 of 18 Posts
M

mrhvacmechanic

· Professional Member*
Joined
·
2,055 Posts
Discussion starter · #1 ·
Can any one tell me how long a ABB vsd has to be left with power off for faults to clear.
Had a mechanic accidentally turn swith from bypass to inverter!!!
No damage done but starter gives a #4 fault indication.Manual says #4 is " Short Circuit" Manual also says that any faults from #1 to #7 are cleared by leaving vsd "VSD OFF FOR A WHILE." Can anyone tell me what off for a while means????
 
#4 ·
Your VSD is considerably newer than ours are. I take it that you have been to ABB-drives.com for additional resources? The drive must think the fault still exists. You have proper supply voltage? Ohmed/meggered motor and leads?
Wish I could be more helpful, I'd be interested to know what you eventually do find. Bob
 
#5 ·
mrhvacmechanic said:

No damage done
Click to expand...
You might want to re-evaluate this statement.

Isolate the fault by disconnecting the motor leads from the drive and power up, if fault goes away you'll look at the motor and associated wiring. A fault of this nature generally means the drive sees a short external to the drive, most modern drives are sophisticated enough to set a different fault is there is an internal problem.
 
Save
Like Like
#7 ·
It's probably an ACH401, the F4 fault is a short circuit. but it is rarely seen by itself, it usually comes with a dc bus voltage problem, try hitting the reset on the keypad and see if you have other faults as well, then check all your input and output wires, if it doesn't clear with the output wires off then you have a bad drive.
 
Discussion starter · #9 ·
Will be on this job Fri morning. I did speak to tech service at ABB and they said leave it off for one hour. As stated above if that doesnt work, disconnect motor and clear fault and see if fault re-appears. If it doesnt, drive is ok but motor may be defective. He said "motor will still run in bypass but in invertermode it can sense a short in motor and motor will still run????????"

BT,
When I ohm motor, will readings be diffrent than a standard 20 HP motor??? I understand that some of these VSD motors are wound or made diffrently than a standard motor?? Is this true??
 
Discussion starter · #11 ·
OK!
First, manual for the drive is#ACS-400.

Second, went to job today after getting approval from customer to do repairs.
Installed a pilot relay for fresh air damper motor with manual pot to adjust quantity.Installed another pilot relay to oprn return air damper before start up of fan.
During this time power was off and I checked motor for shorts and grounds and found none. Motor resistance accross windings was 7 Ohms. Checked all electrical connections and contactors (both accross line and VSD contactor, like new).

Powered up unit and Fault #4 SHORT CIRCUIT was gone and drive showed no falts or alarms. I left the drive in OFF mode and put unit selector switch to " BYPASS" and what do you think happened????????
NO AIR FLOW alarm, motor on bypass was in reversed rotation!!!! Sooooooooooooo I reversed leads at fan fuse block (Assuming drive would still operate, Stupid me!)and I started up fan in bypass again and fan came on in the proper rotation and running a little below rated amperage.

Turned unit to off mode and put selector switch to Inverter mode. Turned unit on and when VSD engauged, the motor started to vibrate as it came up in frquency?????? and was trying to go backwards????
So I said now what??? Well since I reversed at fuse block let met change a phases at Inverter contactor. Now I restarted unit and motor started ramping up in the right direction but there is alot of vibration as it ramps up???
Drive will bring it up but there is defintly something not right?
This vibration is not bearings, belts,alignment,etc.. Its something to do when the drive is ramping up, its like the motor is trying to go both ways, like its STUDDERING.
Left unit in bypass for weekend. The manual is of no use as far as trouble shooting and you have to dial a mess of numbers for ABB info. They dont even respond on their web site! Any suggestions or numbers would be appreciated.
ABB TYPE # AGH401601132
CODE # 64078917
SER# 204010077
Hope I'm using the right manual, customer said it came with unit and McQuay did start-up.

 
#12 ·
Find parameter for ramp time and shorten it... You are seeing harmonics as the drive ramps. You can also program drive to skip certain frequencies that are most troublesome. You might also want to find option to return drive to it's default settings as something may have been changed during the diagnosis. As this is an OEM drive the stock config should match the RTU.
 
Save
Like Like
Discussion starter · #13 ·
Control, thank you for using the proper term, I couldn't think of anything but studdering, lol!

I beleive the proper term is harmonic's. Would you know how this proceedure setting the defaults is done??
Where can I find out about stock configuration and what ramp speed to set up for the motor?

If the defaults are reset will they be the parameters originally set up for the unit??
 
#14 ·
Did you pull the face cover off and check all 4 fuses behind it ?



( 1 is a control fuse 1.5 amps) the others are feeds for the motor during drive oper.,

These fuses are for the drive and are not used in the bypass mode, is the bypass, electronic or manual ?

It still sounds like you have a bad drive ,,, it happens

There is a diode test that you can do to test the preliminary functions of the board in the drive, I don't have the book and don't know if the test is written in the book,

If you can't find it let me know and I will write it and post it.
 
Discussion starter · #15 ·
Ed,
Bypass mode is a standard three pole contactor. I did not open cover of drive. I may be back there on Tues or Wed and I'll open it up. Would't I get a fault if fuses were bad??
 
#16 ·
Yes typically you would, and we can't discount that you did get a fault and now it has cleared for no apparent reason.

While checking the fuses will also allow you to physicaly look at the main boards in the drive also, there may be visibly burned comonents in them, typically the ABB drives will blow out the back of the front board when they fry, I have seen several of them still try to operate in this condition, I guess what I am telling you to do is the first things that the ABB drive tech is going to ask you on the phone, in essence I am just getting you prepared for when you talk to them, I can't fix the drive or troubleshoot them very far past the point that you are at.Although I do startup and program a lot of ABB and Graham Danfoss drives.
 
1 - 18 of 18 Posts
You have insufficient privileges to reply here.
About this Discussion
17 Replies
6 Participants
Last post:
mrhvacmechanic
HVAC-Talk: Heating, Air & Refrigeration Discussion
posts
5M
members
275K
Since
2000
The #1 HVACR Community
Full Forum Listing
Explore Our Forums
AOP Residential HVAC/Refrigeration(Beenthere Zone) General Discussion Tech to Tech Chat - Residential Controls Refrigeration & Ice Making